47 results about "Coulomb damping" patented technology

The invention provides a method for manufacturing a coulomb damped disc brake rotor, including the steps of: (A) providing a mold having the general shape of the coulomb damped disc brake rotor; (B) placing a coulomb damper insert having a generally annular body and at least one tab extending generally radially from the generally annular body, wherein the at least one tab operates to locate the coulomb damper insert within the mold, and wherein the at least one tab at least partially defines an orifice with its major axis generally coincident with the periphery of the coulomb damped disc brake rotor; and (C) causing casting material to enter the mold to substantially encapsulate the coulomb damper insert with the casting material to form a rotor cheek of the coulomb damped disc brake rotor. A coulomb damper insert and coulomb damped disc brake rotor are also disclosed.

Selected surface regions of coulomb vibration damping strips are bonded face-to-face by ultrasonic welding to a surface region of an article that may experience excessive vibration in use. In one embodiment, prior to welding, the intended facing side of the damping strip is treated to form surface regions that are oxidized, roughened, or coating so that the treated regions do not weld to the article surface. In another embodiment of the invention the ultrasonic welding process is controlled so as to produce regions (sometimes randomly interposed regions) of welded and non-welded regions between the damping strip and adjacent article surface. The unbonded regions of the otherwise welded strip lie in closely-spaced, interfacial, frictional contact with the adjacent article surface to damp vibration in the article. Other processes may be used for welding a damping strip to a surface of an article while leaving un-bonded, friction damping regions between regions of the damping strip and the facing surface of the article.

Selected surface regions of coulomb vibration damping strips are bonded face-to-face by ultrasonic welding to a surface region of an article that may experience excessive vibration in use. In one embodiment, prior to welding, the intended facing side of the damping strip is treated to form surface regions that are oxidized, roughened, or coating so that the treated regions do not weld to the article surface. In another embodiment of the invention the ultrasonic welding process is controlled so as to produce regions (sometimes randomly interposed regions) of welded and non-welded regions between the damping strip and adjacent article surface. The unbonded regions of the otherwise welded strip lie in closely-spaced, interfacial, frictional contact with the adjacent article surface to damp vibration in the article. Other processes may be used for welding a damping strip to a surface of an article while leaving un-bonded, friction damping regions between regions of the damping strip and the facing surface of the article.

The invention provides a metal rubber-disc spring full metal composite hanging bracket for vibration isolation and impact resistance of a pipeline. The metal rubber-disc spring full metal composite hanging bracket comprises metal rubber net cushions, disc-shaped springs, and a press cover, guide rods, bearing bolts and a shell which are used for supporting and fixing the elastic elements, and also comprises an extending rod, a universal spherical hinge and the like which are connected with the pipeline. The complex flexible and hard rigidity characteristics and large damping are realized by using the large bearing capacity and the flexible rigidity characteristic of the disc springs, the coulomb damping among the disc springs, the hard rigidity characteristic of the metal rubber net cushions, the coulomb damping among the disc springs and the metal rubber net cushions, and the air damping in the gaps between the guide rods and the bearing screw nuts. The metal rubber-disc spring full metal composite hanging bracket for the vibration isolation and impact resistance of the pipeline is compact in structure, light in weight and high in high-temperature environment adaptation, has higher static rigidity, lower dynamic rigidity and excellent damping property, is lower in vibration isolation frequency and is automatically limited, both the impact isolation and limiting functions are considered, and the impact acceleration response and the impact displacement response can be controlled in a reasonable range.

The present invention is directed to three dimensional weaves composed of wires or yarns that offer the potential for damping not achievable with solid materials, including high temperature damping. Three damping mechanisms have been identified: (1) Internal material damping, (2) Frictional energy dissipation (Coulomb damping), and (3) inertial damping (tuned mass damping). These three damping mechanisms can be optimized by modifying the wire material chemistries (metals, ceramics, polymers, etc.), wire sizes, wire shapes, wire coatings, wire bonding, and wire architecture (by removing certain wires). These have the effect of modifying the lattice and wire stiffnesses, masses, coefficients of friction, and internal material damping. Different materials can be used at different locations in the woven lattice. These design variables can also be modified to tailor mechanical stiffness and strength of the lattice, in addition to damping.

The invention discloses a whirling control method of the rotor of a mini-size turbojet engine, which is characterized in that in the scalar system, the axial pre-tightening force or the waveform gasket compression amount, the waveform gasket rigidity, the rotor speed, the rotor quality and the unbalance information are adopted to accurately compute the thickness, the quantity and mounting mode ofthe coulomb damp gasket for the attenuation whirling through the energy equivalent theory; the damping rubber is combined to adjust the damping of the rotor and mount structurally; thereby, the whirling of the engine rotor is controlled accurately and the stable operation requirement under the higher rotational speed is realized for the mini-size turbojet engine. The whirling control method of therotor of a mini-size turbojet engine has the advantages of accurate coulomb damping computation, accurate whirling attenuation control, simple damp structure, light weight and convenient adjustment,wide application range, being applicable to the different forms of whirling of the mini-size turbojet and the whirling under the different frequencies.

The invention relates to a control algorithm of an automotive magneto-rheological semi-active suspension system and real-time optimal current, and belongs to the technical field of dampers. The control algorithm is characterized by comprising the steps that damping characteristics of a magneto-rheological damper and the semi-active suspension system are simulated according to the currently measured current; the current running road condition of an automobile is identified according to the running speed and the vibration acceleration of an automobile body; a real-time optimal damping ratio of the semi-active suspension system and an optimal Coulomb damping force of the magneto-rheological damper are determined according to the current running road condition, and speed and suspension parameters; and the real-time optimal control current of the automotive magneto-rheological semi-active suspension under the current running working condition is calculated according to relations among the Coulomb damping force, a structure parameter, a magneto-rheological liquid characteristic parameter, the turn number of an electromagnetic coil and the current. According to the control algorithm, a design level and the performances of the magneto-rheological semi-active suspension system can be raised and improved; design and testing expenses are lowered; and the running smoothness and the safety of the automobile are improved.

The invention relates to an order-variable permanent magnet rheological damper and belongs to the field of mechanical vibration engineering. The order-variable permanent magnet rheological damper is a non-power-supply damping vibration absorber. The on-off states of a permanent magnet circuit are controlled by changing the magnetic permeability and the axial effective length of an inner cylinder tube, so that the output damping force, changing along with the piston stroke, of the permanent magnet rheological damper is adjusted, order-variable output of coulomb damping force is achieved, preset damping force is obtained, and effective shock absorption is conducted. An inner cylinder tube section of the order-variable permanent magnet rheological damper is formed by fixedly connecting one section of magnetic-permeability material cylinder tube and two sections of non-magnetic-permeability material cylinder tubes, and a permanent magnet structure piston is a multilevel electromagnetic circuit. The permanent magnet rheological damper is free of energy consumption, simple in structural design and high in stability and has other shock absorption properties.